A report by the Prisons and Probation Ombudsman (PPO), who investigates deaths in custody, highlighted a number of problems in relation to establishments holding 18- to 24-year-olds, including weak risk assessments and issues with bullying.
Out of a total of 80 deaths of 18- to 24-year-olds in custody since 2007 PPO Nigel Newcomen found that one in five had been bullied in the month before their death, compared to 13 per cent of all prisoners.
In addition, risk assessments and monitoring of vulnerable young people were in need of improvement and staff routinely failed to act on concerns about the emotional wellbeing of offenders raised by family members.
Among his recommendations is for prisons to take a tougher stance when allegations of bullying are made and consider the risk of suicide among victims.
Other recommendations include better referrals for mental health treatment, a recognition that transfers across the secure estate can have a negative effect on vulnerable prisoners and a better understanding that challenging behaviour can be an indicator of suicide risk.
He found that too often challenging behaviour was dealt with through tough sanctions, without taking into account it being a potential indicator of mental health problems and suicide risk.
Newcomen said: “Young adults can be difficult and challenging, as well as potentially vulnerable, population to manage.
"In our sample challenging behaviour was common, with prison records detailing warnings for poor behaviour, formal adjudications and punishments for breaches of prison rules.
“I hope our findings make a significant contribution to greater safety in custody.”
Deborah Coles, co-director of the charity Inquest, which works with bereaved families, said the report was “depressingly familiar reading”.
She said: “These deaths are the most extreme outcome of a system that fails some of society’s most troubled and disadvantaged young people, many just out of childhood.
"The young people we incarcerate are some of the most vulnerable with histories of mental ill-health, drug and alcohol problems, learning difficulties, abuse, and trauma.”
Chief executive of the Howard League for Penal Reform, Frances Crook, added: “This bleak compilation of tragedies sets out in shocking detail how young adults, and especially those with mental health problems, are left to suffer in institutions where violence is rife and bullying is commonplace.
“Prisoners are dying for want of a radio to listen to or a book to read. Cries for help are going unheard.
"Families’ concerns are being ignored. It is a shocking indictment of the state’s approach to people in trouble.”